GaAs MOSFET using MBE-grown Ga2O3 (Gd2 O3) as gate oxide

An enhancement mode GaAs metal-oxide-semiconductor field effect transistor (MOSFET) with Ga₂O₃ (Gd₂O ₃) as gate dielectric has been successfully fabricated. The low interface density Ga₂O₃ (Gd₂O₃ ) oxide and GaAs n-channel layer were grown by in situ molecular beam epitaxy (MBE). The fabricated n-channel MOSFET with 20 nm-thick oxide and 2 μm-long gate operated both in enhancement and depletion modes, with a peak transconductance of 40 mS/mm in the enhancement mode. While operating with gate voltages ranging from -1 to 5 V, the device showed a drain current drift of 10.5% for a duration of 10⁴s, a limited amount of hysteresis and negligible dispersion of transconductance from 10 Hz to 1 MHz